The experience on a virtual reality headset is downright mind-blowing, and it’s also soon after that you seriously question the possibility of life being one big computer simulation.
Given the logically compelling arguments, it really isn’t too much of a bat-crap crazy concept to think that the reality we experience is being simulated on a computer.
Computers have been getting fast and smart. According to researchers who run Harvard’s Odyssey supercomputer, it’s possible to simulate a universe on a supercomputer. And guess what? Their supercomputer can simulate the 13.8 billion years from scratch in only a few months.
* Arepo accurately follows the birth and evolution of thousands of galaxies over billions of years.*
What it does is use a reshaping grid; which fills itself with various amounts of tetrahedrons to form the different components of the universe. The more components any part of the universe contains the denser the region. Regardless of the specifics (which you can read about on Discovery) this goes to show the possibility of simulating a* universe-like* environment on a computer.
Now if you were to ask why anyone would ever want to simulate a universe? It could be that scientists needed one to run tests on humanity for the benefit of their own world. Physicists and biologists already do such simulation at smaller scales (e.g. Disease Epidemic Models). Or it could also be the case that someone just created it for fun… or if I may:
If you’re thinking that we’d definitely know if it were a simulation – imagine putting your brain in a biochemical vat and simulating it with electrical signals to keep it alive and functioning. As long as it’s being stimulated right there would be no reason for the brain to know it’s in a chemical vat. In the same sense, an advanced enough simulator would certainly mean that it’s inhabitants would be oblivious to the fact that they’re all just a simulation on a computer.
There’s also a mathematical explanation to this. The logician Kurt Gödel argued that mathematical concepts and ideas “form an objective reality of their own, which we cannot create or change, but only perceive and describe.” This could be used to suggest that if we were to be living in a computer simulation based on the laws of mathematics, each time we discover a mathematical truth is when we’re discovering some part of the code used to create the simulation.
In fact three physicists (Silas R. Beane, Zohreh Davoudi and Martin J. Savage), have used three-dimensional grid models (similar to Arepo) to simulate chunks of the universe for many year. According to their paper published in 2012, they observed certain kinds of asymmetries which were small yet distinct anomalies in the simulations. This led them to wonder if we might see such anomalies in the real universe? The paper suggests that a closer look at cosmic rays (high energy particles travelling through space) may reveal similar asymmetries, in which case we just might discover that the universe we currently inhabit is one big computer simulation!
This is the contradiction between the high estimates of the existence of extraterrestrial civilizations and the lack of evidence for such civilizations. The argument discusses the following (source: Wikipedia):
- The Sun is a typical star, there are billions of stars on the universe that are older than the sun.
- With high probability, some of these stars will have Earth-like planets.
- Some of these civilizations might develop interstellar travel, a step the Earth is investigating now.
- Even at the slow pace of currently envisioned interstellar travel, the Milky Way galaxy could be completely traversed in about a million years.
*So where is everybody? *One counterargument could be that intelligent extraterrestrial life is so rare and so brief that humans would never make any contact. But it’s a conflict between arguments of scale and probability that seem to favor intelligent life being common in the universe, and since there is no conclusive evidence of intelligent life after 13.8 billion years of the universe’s history, there must be another explanation. Right?
That was enough of a thought twist for my week. How about you?
I like to keep my articles concise and to the point, if you’re interested in this topic checkout my sources for further reading:
 Complete Arepo simulation
 Fermi’s paradox on Wikipedia:
 Is the Universe a Simulation? – The New York Times
 The Singularity: A peek into an unfathomable future